Delivery pipe for hydraulic dredging machines



Ap.10, 1923. v 1,451,272 I A. W. ROBINSON DELIVERY PiE FOR HYDRAULIC DREDGING MACHINES Filed oct. 1. i921 l l Afro/MY Patented Apr. l0, 1923.

o i Ar ARTHUR w. ROBINSON, or MONTREAL, QUEBEC, CANADA.

DELIVERY PIPE FOR HYDRAULIC DREDGING MACHINES.

Application filed October 1, 1921. v SerialiNo. 504,809.

dredging machine or other source of supply to the place of deposit by being pumped through a delivery pipe, together 'with av suitable admixture of water.

It is the purpose of this invention to obviate a serious difhculty experienced in the use of hydraulic dredging machines of the class stated which is that the spoils as they are pumped through the delivery pipe fre-A quently tend` to lodge and become fixed in the delivery pipe to such an extent as to 'seriously restrict the passage through the pipe and sometimes even to lclog it entirely or to such an extent as to seriously interfere with the operation of the machine and inevitably requiring a material increase in the power necessary.

Itis the purpose of this invention, therefore, to obviate the stated difficulty by preventing the spoils during their passage through the pipe from accumulating or depositing themselves upon its bottom in such manner or to such a degree as will clog that same or interfere with the proper operation of the apparatus. In other words, under this invention the spoils in their passage through the delivery pipe are continually brought from the lower sections of the pipe to the upper sections thereof, and in their attempt to fall under the action of gravity to the lower sections of the pipe they are inevitablyl maintained in a condition of practically homogeneous mixture with the propelling water so that all lodgment in the bottom of the pipe is prevented and the power required to effect the desired delivery is materially reduced.

Referring to the drawing. Fig. l illustrates a longitudinal view of a section of so called shore pipe partly in sections showing the invention.

Fig. 2 illustrates a transfer sectional view taken on the line 2.2. of Fig. 1.

In the drawings hereof I illustrate the invention as applied to a section of what is known as shore pipe, that is to say, a. sectional pipe which being ,used Auponthe land in contradistinction to that `which is used upon ioats,` does not require the usual ball and socket or equivalent connection between the lengths ofv pipe; on the contrary are merely telescoped` together somewhat after:

the fashion of ordinary stovepipe.

It will, of course, be understood that the invention is as applicable to floating pipes as to shore pipes, since the construction and method of operation, so far as this invention is concerned, are identical in both cases.

In the drawings l. illustrates the pipe .2, whatI shall call in this specification rifling ribs because they. have substantially ythe sameeifect upon the spoils during their.

passage through the pipe that the rifiing of a cannon or riflel have upon the bullet or shell during its passage through the bore of i the arm, that is to say,lthey give the water and the spoils carried by it a pronounced` longitudinally of the pipe and radially from its interior surface inwardly. They,

may be made in any preferred form,vand of such width as desired. I lprefer them to be made of relatively hardsteel, and in the form of the angle iron shown, that is to say, having one radial member 3 and a base member 4;, the base member being bolted or otherwise, suitably fastened to the interior surface of the pipe. There'may be as many of these rifling ribs employed in the pipe as desired. I ordinarily prefer three as illustrated. Their number, however, will depend to some extent upon the character of the spoils being excavated and the power of the pump in propelling the water. In exceptional cases a single rib only may serve the purpose, in other cases two, three or more may secure the best results, and I prefer that they should have adegree of spirality equal to from 15 to 25 times thediametervof the pipe, that is to say, in a section of shore pipe which, for example, may be twent feet long, each of the rifle ribs may ma e one loo space between them. Also they may be omitted altogether in the bottom of the pipe so as to permit stones to more readily pass.

In order that there may be no possibility of the dredged material which sometimes, particularly in the case of harbor dredging, may include pieces of rope, wire, chain and other similar material from becoming lodged over the front end of the rifle ribs, I prefer to bevel oil both the base member 4 Iand the vertical or radial member 3, at their front end, that is to say, at the end first encountered by theV spoils in their passage through the pipe, as shown at 5.

The operation is obvious as the pump forces the spoils which are puddled with a large percentage of water through the pipes, the radial riiie ribs Will successively cause the current of water 'to follow a violent spiral or whirling course through the pipes, which, of course. will catch and carry with it all of the spoils excepting perhaps the heavier parts, such as Cobble stones and the like, `and will carry them tothe upper party of thepipe and under the action of gravity they will attempt to tall through `the spirally flowing current, but being caught `thereby will be maintained in the upper and central portions of the pipe and be prevented from depositing themselves in the lower portions'as heretofore. Consequently, all lodgment of the spoils vwhich heretofore have created the trouble will be avoided and so far. as the heavier elements, that is to say, Cobble stones and the like, are concerned there never has been any diiliculty in their delivery because the pumped currentis so powerful that owing to their bulk they are rolled along and in due course delivered at the mouth of the pipe. The rifle ribs will, of course, be made of sufficient strength and solidity to withstand the blows delivered upon them by the heavier material referred to.

It will be obvious to those who are ifainiliar with such matters that the riile ribs may be made in a Variety of ways and oic such radial width and degree of spirality, and as stated above, of such number as preferred, and that they may be built into or applied to the pipe also insuch manner as may be preferred, and that various modi-k fications may be made in the details of construction without departing from the essentials of my invention.

l claimln a delivery pipe for hydraulic dredges a radially and spirally arranged rifling rib made of rolled angle' iron and extending from end to end of the pipe, one angle arranged radially ot the pipe, the-other acting as a base and immovably fastened to the interior of the pipe, the front end of the radial angle being beveled off.

ARTHUR WQ RoBiNsoN. 

